1. Field of the Invention
The present invention relates to a dual-standby mobile terminal. More particularly, the present invention relates to a neighbor cell monitoring method and apparatus for a dual-standby mobile terminal that is capable of reducing unnecessary power consumption.
2. Description of the Related Art
Recently, multi-standby mobile terminals, which allow a subscriber to receive calls through different communication networks with multiple Subscriber Identity Modules (SIMs), are emerging in the market. As a representative multi standby mobile terminal, a dual-standby GSM (Global System for Mobile telecommunication) mobile terminal is well-known.
The dual-standby GSM mobile terminal (hereinafter, called just ‘mobile terminal’) is implemented with two sets of function modules operating on two different GSM frequency bands. That is, the dual-standby mobile terminal includes a pair and core modules, a pair of power management module, a pair of memory modules, a pair of Radio Frequency (RF) modules, and a pair of SIM, and these paired function modules constituting two individual GSM communication units.
The two GSM units can be configured to operate with common functional units including, for example a display unit, a keypad, a battery, and the like. Also, the two GSM units can communicate through an interface such as a Dual Port Random Access Memory (DPRAM) interface. The two GSM units can operate as individual mobile terminals: one as the master GSM unit and the other as the slave GSM unit. Since the master and slave GSM units operate individually, the two units also perform main cell tracking and neighbor cell monitoring simultaneously. Such overlapped actions are continued in most operational processes including cell selection, cell reselection, and handover, as well as in the initial power-on of the dual-standby GSM mobile terminal.
Meanwhile, a mobile terminal acquires neighbor cell information from the cell on which the mobile terminal has camped. In case that the dual standby GSM mobile terminal has camped on a specific cell, the master and slave GSM units simultaneously receive the same neighbor cell information provided by the cell.
More particularly, the master and slave GSM units of the dual-standby GSM mobile terminal receive the same neighbor cell list from the same cell, and this means information redundancy. From the viewpoint of the mobile terminal, the overlapped operations of the master and slave GSM units to acquire the same neighbor cell list causes unnecessary resource and power waste.
As mentioned above, the conventional dual-standby mobile terminal is configured such that the master and slave units perform neighbor cell monitoring simultaneously to acquire the same neighbor cell list.
Such overlapped operations of the master and slave units of a mobile terminal increase the RF processing load and power consumption, resulting in unnecessary resource and energy waste by the duplicated operation.